Rear Differential Clutch Packs

Anyone here ever changed out clutch packs in an LSD rear end? I have a 2008 TRD sport with a neglected rear end. I don't think I changed the fluid until 150k miles... Anyway, I've changed it twice since then, using the additive and it still seems to bind when cold. Maybe the clutch packs are just worn out...I don't know. I added half of a second bottle of additive and it got some better, but I can still feel it binding.

 

Used to be a common problem years ago but what we used to do is drive tight figure 8's in a parking lot.

 

My kid had a jeep J10 with "quadra-track" - an always engaged transfer case with a limited slip between the front and rear drive shafts. Big block Chev twisted off the input and I replaced it. Jeep book said to use ashless 30wt and "friction modifier" to fill case. Went to dealer parts desk and found the stuff was replaced by mopar brand " quadra-track" fluid at $30.00 per qt. So being a hard case I went for the 30wt and called a friend who is lubrication engineer. He sent me to Chev parts counter for GM "positraction" fluid - 4 ozs. Said to add the friction modifier a little at a time until we had just the right amount of slip to make it work smoothly. Worked like champ after a couple of tries.

I'd say the same applies here - add more friction modifier until the unit slips enough to suit you.

 

GM positraction additive used to contain whale oil and it actually did something but it has not been used in decades. If it's hopping the pack is not worn out they are sticking together. I believe I would start with a fluid change and use Toyota recommended fluid.

 

ACDelco 10-4003 Limited Slip Axle Lubricant Additive - 4 oz - $7.73 on Amazon

The point is - if the specified Toyota additive made the situation better - try some more, can't hurt.

 

That's what I'm thinking. I put a whole bottle of modifier in last time I changed the fluid. Then recently I drained some out and put another half a bottle in...that just doesn't seem right.

 

I finally decided to just start over with a different brand of oil and modifier. I used the cheapest Valvoline (dino) oil and the Motorcraft XL-3 modifier. All of the binding seems to be gone...I guess mine didn't like the Lucas Oil or the Trans-x modifier.

 

My 07 would chatter on synthetic gear oil, I tried synthetic once (funny enough...it was Lucas 75w90) and never again. I added extra friction modifier to it before I dumped it and could not get it to stop chattering. After that it was always cheap 80w90 for the rear diff with 4oz of LS additive, no issues after going back to 80w90 conventional.

 

supposedly the LSD prefers regular gear oil and not synthetic, with some friction modifier added

 

I'm pretty sure the Lucas oil I used was not synthetic...still not sure what the problem was. Working good with the new stuff.